(a) In general
During fiscal year 2014 and any succeeding fiscal year, the Librarian of Congress may transfer amounts appropriated for the fiscal year between the categories of appropriations provided under law for the Library of Congress for the fiscal year, upon the approval of the Committees on Appropriations of the House of Representatives and Senate.
Not more than 10 percent of the total amount of funds appropriated to the account under any category of appropriations for the Library of Congress for a fiscal year may be transferred from that account by all transfers made under subsection (a).
2 U.S.C. § 132a-3 (2018)